package com.superatom.concurrent.basic.priority;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * 设置优先级在Mac中没什么效果体现
 * 在windows有效果
 */
public class SimplePriorities implements Runnable{
    private int countDown = 5;
    private volatile double d;
    private int priority;

    public SimplePriorities(int priority){
        this.priority = priority;
    }

    public String toString(){
        return Thread.currentThread() + ": " + countDown;
    }


    public void run() {
        Thread.currentThread().setPriority(priority);

        while (true){
            // 模拟线程开销
            for (int i = 0; i < 100000; i++){
                d += (Math.PI + Math.E) / (double) i;
                if ( i % 1000 == 0){
                    Thread.yield();
                }
            }

            System.out.println(this);
            if (--countDown == 0)
                return;
        }
    }

    public static void main(String[] args){
        ExecutorService exec = Executors.newCachedThreadPool();
        for (int i = 0; i < 5; i++){
            exec.execute(new SimplePriorities(Thread.MIN_PRIORITY));
        }

        exec.execute(new SimplePriorities(Thread.MAX_PRIORITY));
        exec.shutdown();
    }
}
